Sama-sam-buddha = One who rediscovers the teachings and teaches the masses as the historical Buddha did (Siddhattha Gotama).

Paccekabuddha = A silent buddha. One who attains full enlightenment, but does not teach others. He attains enlightenment during a time when there is no Dhamma dispensation.

Arahant = Fully enlightened person, who might teach others, but not as the one who rediscovered the teachings, just as one who learned it from a current dispensation.

All are fully enlightened, hard to attain. But simply using statistics, the Arahant would be the "easiest" to attain of the three above. Samma-sam-buddhas and Pacceka-buddhas are very rare, but there were several thousand monks and nuns (and a few lay people) who attained full enlightenment during the Buddha's lifetime, as recorded in the Pali Canon.

Higher than the Paccekabuddhas are the Sammasambuddhas because of the greatness of their virtue: “For even (a group of) Paccekabuddhas seated on the whole of the (continent of) Jambudipa so close together that sitting cross-legged (their knees) would touch each other, do not attain a portion, or a sixteenth part or a small fraction (of that) of the virtues of one perfectly enlightened one” (I 177–178).

this was better: A distinction between the knowledge (ñana) of disciple, Paccekabuddha and Buddha is made in the Saratthappakasini, where the Buddha is shown admonishing Ananda thus: “Why did you not penetrate the knowledge of the perfections of a disciple like Sariputta and Moggallana, who fulfilled the perfections in the course of one hundred thousand kalpas plus one incalculable period, and (why) did you not penetrate the knowledge of self-enlightenment like the Paccekabuddhas who fulfilled the perfections in the course of one hundred thousand kalpas plus two incalculable periods?” (S-a II 93).

David N. Snyder wrote:Sama-sam-buddha = One who rediscovers the teachings and teaches the masses as the historical Buddha did (Siddhattha Gotama).

Paccekabuddha = A silent buddha. One who attains full enlightenment, but does not teach others. He attains enlightenment during a time when there is no Dhamma dispensation.

Arahant = Fully enlightened person, who might teach others, but not as the one who rediscovered the teachings, just as one who learned it from a current dispensation.

All are fully enlightened, hard to attain. But simply using statistics, the Arahant would be the "easiest" to attain of the three above. Samma-sam-buddhas and Pacceka-buddhas are very rare, but there were several thousand monks and nuns (and a few lay people) who attained full enlightenment during the Buddha's lifetime, as recorded in the Pali Canon.

I would of agreed fully with each of these a couple of months ago, but there has been a fairly recent paper on the Paccekabuddha that shows they do teach.I heard a while ago (3+years) that there is a sambuddha also (yes minus the samma) that teaches but it doesn't last a long time (in a Ajahn Vajiro talk on the perfections). they taught only what was needed through supernormal powers so didn't need to give detailed instructions on a techneque, they only needed to say do this & that and the job was done teaching wise.

He who knows only his own side of the case knows little of that. His reasons may be good, and no one may have been able to refute them. But if he is equally unable to refute the reasons on the opposite side, if he does not so much as know what they are, he has no ground for preferring either opinion … ...He must be able to hear them from persons who actually believe them … he must know them in their most plausible and persuasive form.John Stuart Mill